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1.
Phys Rev Lett ; 125(14): 141301, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33064531

RESUMO

We present the first Ge-based constraints on sub-MeV/c^{2} dark matter (DM) particles interacting with electrons using a 33.4 g Ge cryogenic detector with a 0.53 electron-hole pair (rms) resolution, operated underground at the Laboratoire Souterrain de Modane. Competitive constraints are set on the DM-electron scattering cross section, as well as on the kinetic mixing parameter of dark photons down to 1 eV/c^{2}. In particular, the most stringent limits are set for dark photon DM in the 6 to 9 eV/c^{2} range. These results demonstrate the high relevance of Ge cryogenic detectors for the search of DM-induced eV-scale electron signals.

2.
Mol Biol (Mosk) ; 53(2): 179-199, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31099770

RESUMO

At present, pharmacologically significant proteins are synthesized in different expression systems, from bacterial to mammalian and insect cell cultures. The plant expression systems (especially suspension cell culture) combine the simplicity and low cost of bacterial systems with the ability to perform eukaryotic-type posttranslational protein modifications. A low (compared with bacterial systems) yield of the target recombinant protein is one of the shortcomings of the plant expression systems. In this review, methods, developed over the past two decades, to increase the level of recombinant gene expression and methods to prevent silencing, caused by a random insertion of the target gene into heterochromatin region, are considered. The emergence of CRISPR/Cas technologies led to the creation of a new approach to increase the gene expression level, directional insertion of "pharmaceutical" protein genes in specific, knowingly transcriptionally active genome regions. The plant cell housekeeping gene loci, actively expressed throughout the interphase, are these regions. The organization of some housekeeping genes, most promising for transferring recombinant protein genes in their loci, is considered in detail.


Assuntos
Edição de Genes/tendências , Células Vegetais/metabolismo , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Animais , Sistemas CRISPR-Cas/genética , Genes Essenciais/genética
3.
Biochemistry (Mosc) ; 83(3): 215-232, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29625542

RESUMO

Most the pharmaceutical proteins are derived not from their natural sources, rather their recombinant analogs are synthesized in various expression systems. Plant expression systems, unlike mammalian cell cultures, combine simplicity and low cost of procaryotic systems and the ability for posttranslational modifications inherent in eucaryotes. More than 50% of all human proteins and more than 40% of the currently used pharmaceutical proteins are glycosylated, that is, they are glycoproteins, and their biological activity, pharmacodynamics, and immunogenicity depend on the correct glycosylation pattern. This review examines in detail the similarities and differences between N- and O-glycosylation in plant and mammalian cells, as well as the effect of plant glycans on the activity, pharmacokinetics, immunity, and intensity of biosynthesis of pharmaceutical proteins. The main current strategies of glycoengineering of plant expression systems aimed at obtaining fully humanized proteins for pharmaceutical application are summarized.


Assuntos
Glicoproteínas/química , Glicoproteínas/metabolismo , Preparações Farmacêuticas/metabolismo , Plantas/metabolismo , Engenharia de Proteínas , Glicoproteínas/genética , Glicosilação , Humanos , Preparações Farmacêuticas/química , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/genética
4.
Br J Dermatol ; 176(5): 1213-1223, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27542662

RESUMO

BACKGROUND: Recent reports have indicated that nonimmune cells can produce low concentrations of histamine. This observation, together with the discovery of the high-affinity histamine H4 receptor (H4 R), has added additional layers of complexity to our understanding of histamine signalling. Human oral keratinocytes (HOKs) possess a uniform H4 R pattern, which is deranged in oral lichen planus (OLP). OBJECTIVES: To investigate histamine metabolism and transport in HOKs of healthy controls and patients with OLP. METHODS: Tissue sections and cultured primary HOKs were studied using immunostaining, quantitative real-time polymerase chain reaction and confocal microscopy. Histamine levels were analysed using high-performance liquid chromatography. RESULTS: l-histidine decarboxylase (HDC) and organic cation transporter (OCT)3 were increased in mRNA and protein levels in patients with OLP compared with controls. In contrast, histamine N-methyltransferase (HNMT) immunoreactivity was decreased in OLP. OCT1/OCT2 and diamine oxidase were not detectable in either tissue sections or in HOKs. Immunolocalization of HDC and OCT3 in HOKs revealed moderate-to-high expression within cytoplasm and cell boundaries. Stimulation with lipopolysaccharide (LPS) or interferon-γ upregulated HDC-gene transcript in HOKs, whereas this was downregulated with high histamine concentration and tumour necrosis factor-α. LPS induced a dose-dependent release of low histamine in HOKs, while high histamine concentration downregulated epithelial adhesion proteins. CONCLUSIONS: HOKs are histamine-producing cells. They release histamine via OCT3 channels in concentrations too low to activate the classical low-affinity H1 R and H2 R, but high enough to stimulate the high-affinity H4 R in autocrine and paracrine modes. The substantially deranged histamine metabolism and transport in OLP could, in part, contribute to the disease pathogenesis.


Assuntos
Histamina/metabolismo , Queratinócitos/metabolismo , Líquen Plano Bucal/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Amina Oxidase (contendo Cobre)/metabolismo , Células Cultivadas , Citosol/metabolismo , Regulação para Baixo/fisiologia , Histamina N-Metiltransferase/metabolismo , Histidina Descarboxilase/metabolismo , Humanos , Interferon gama/farmacologia , Líquen Plano Bucal/etiologia , Lipopolissacarídeos/farmacologia , Pessoa de Meia-Idade , Proteínas de Transporte de Cátions Orgânicos/metabolismo , RNA Mensageiro/metabolismo , Regulação para Cima/fisiologia , Adulto Jovem
5.
Dev Biol ; 370(2): 237-49, 2012 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-22898306

RESUMO

Mesencephalic astrocyte derived neurotrophic factor (MANF) is recognized as a dopaminergic neurotrophic factor, which can protect dopaminergic neurons from neurotoxic damage. However, little is known about the function of MANF during the vertebrate development. Here, we report that MANF expression is widespread during embryonic development and in adult organs analyzed by qPCR and in situ hybridization in zebrafish. Knockdown of MANF expression with antisense splice-blocking morpholino oligonucleotides resulted in no apparent abnormal phenotype. Nevertheless, the dopamine level of MANF morphants was lower than that of the wild type larvae, the expression levels of the two tyrosine hydroxylase gene transcripts were decreased and a decrease in neuron number in certain groups of th1 and th2 cells in the diencephalon region in MANF morphants was observed. These defects were rescued by injection of exogenous manf mRNA. Strikingly, manf mRNA could partly restore the decrease of th1 positive cells in Nr4a2-deficient larvae. These results suggest that MANF is involved in the regulation of the development of dopaminergic system in zebrafish.


Assuntos
Neurônios Dopaminérgicos/citologia , Fatores de Crescimento Neural/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/embriologia , Animais , Encéfalo/citologia , Encéfalo/embriologia , Encéfalo/metabolismo , Neurônios Dopaminérgicos/metabolismo , Embrião não Mamífero/embriologia , Embrião não Mamífero/metabolismo , Proteínas de Homeodomínio/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Morfolinos/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neuropeptídeos/metabolismo , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares/genética , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares/metabolismo , Orexinas , Fator de Transcrição PAX2/metabolismo , Receptor Notch1/metabolismo , Serotonina/metabolismo , Fatores de Transcrição/metabolismo , Peixe-Zebra/metabolismo , Ácido gama-Aminobutírico/metabolismo
6.
Pharmacol Ther ; 221: 107741, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33189715

RESUMO

Several studies have demonstrated the effectiveness of ketamine in rapidly alleviating depression and suicidal ideation. Intense research efforts have been undertaken to expose the precise mechanism underlying the antidepressant action of ketamine; however, the translation of findings into new clinical treatments has been slow. This translational gap is partially explained by a lack of understanding of the function of time and circadian timing in the complex neurobiology around ketamine. Indeed, the acute pharmacological effects of a single ketamine treatment last for only a few hours, whereas the antidepressant effects peak at around 24 hours and are sustained for the following few days. Numerous studies have investigated the acute and long-lasting neurobiological changes induced by ketamine; however, the most dramatic and fundamental change that the brain undergoes each day is rarely taken into consideration. Here, we explore the link between sleep and circadian regulation and rapid-acting antidepressant effects and summarize how diverse phenomena associated with ketamine's antidepressant actions - such as cortical excitation, synaptogenesis, and involved molecular determinants - are intimately connected with the neurobiology of wake, sleep, and circadian rhythms. We review several recently proposed hypotheses about rapid antidepressant actions, which focus on sleep or circadian regulation, and discuss their implications for ongoing research. Considering these aspects may be the last piece of the puzzle necessary to gain a more comprehensive understanding of the effects of rapid-acting antidepressants on the brain.


Assuntos
Antidepressivos , Ketamina , Antidepressivos/farmacologia , Ritmo Circadiano/efeitos dos fármacos , Humanos , Ketamina/farmacologia , Sono/efeitos dos fármacos , Fatores de Tempo , Vigília/efeitos dos fármacos
7.
Prikl Biokhim Mikrobiol ; 43(3): 265-71, 2007.
Artigo em Russo | MEDLINE | ID: mdl-17619572

RESUMO

The review sums up the long experience of the authors and other researchers in studying the genetic system of garden pea (Pisum sativum L.), which controls sthe development of nitrogen-fixing symbiosis and arbuscular mycorrhiza. A justified phenotypic classification of pea mutants is presented. Progress in identifying and cloning symbiotic genes is adequately reflected. The feasibility of using double inoculation as a means of increasing the plant productivity is demonstrated, in which the potential of a tripartite symbiotic system (pea plants-root nodule bacteria-arbuscular mycorrhiza) is mobilized.


Assuntos
Bactérias/genética , Micorrizas/genética , Fixação de Nitrogênio/genética , Pisum sativum/genética , Nódulos Radiculares de Plantas/genética , Simbiose/genética , Mutação , Nódulos Radiculares de Plantas/microbiologia
8.
Mol Biol (Mosk) ; 16(4): 703-11, 1982.
Artigo em Russo | MEDLINE | ID: mdl-7121458

RESUMO

Lysine-rich histone H1 of animals from three reptilian orders was studied. Electrophoretically pure H1 histone subfractions were cleaved at residues of tyrosine, methionine, aspartic acid and phenylalanine. The fragments obtained were studied by modified method of incomplete succinylation which permitted to determine the number of lysine residues, the positive charge and molecular length of polypeptides. The structural homology between the fastest reptilia H1 subfraction and avian H5 histone has been shown.


Assuntos
Aves/genética , Histonas/genética , Répteis/genética , Sequência de Aminoácidos , Animais , Peso Molecular , Fragmentos de Peptídeos/análise , Especificidade da Espécie
9.
Mol Biol (Mosk) ; 16(4): 790-8, 1982.
Artigo em Russo | MEDLINE | ID: mdl-7121462

RESUMO

Five electrophoretic variants of H5 histone were detected in the population of linnet (Acanthis flammea). Using the method of incomplete succinilation the number of lysine residues, electrophoretic positive charge and molecular length were determined for some variants of H5 histone and for their fragments, obtained after treatment with n-bromosuccinimide and chymotrypsin. The difference in structure of H5 variants was found to be connected with the region, confined by the phenylalanine residue and the C-end of the molecule. The minimal difference in molecular length of fragments carrying the variable region was found to be 6 amino acids, two of them are basic. A series of "regular" fragments was detected after mild treatment with trypsin. The number of these fragments increased in parallel with the increase of histone length. In accordance with the scheme proposed, the difference in structure of linnet H5 variants is caused by insertion of the regular region consisting of tandem repeats (from 3 to 7 times) of the elementary hexapeptide.


Assuntos
Variação Genética , Histonas/genética , Plantas/genética , Bromosuccinimida , Quimotripsina , Peso Molecular , Fragmentos de Peptídeos/análise , Tripsina
10.
Mol Biol (Mosk) ; 18(6): 1497-508, 1984.
Artigo em Russo | MEDLINE | ID: mdl-6441113

RESUMO

Sperm of freshwater bivalve mollusk Anodonta piscinalis was found to contain two fractions of lysine-rich histone: somatic histone H1 and sperm-specific protamine-like histone, named Hp. A detailed analysis of H1 and Hp structure was carried out by means of N-bromosuccinimide, chymotrypsin and pepsin cleavage followed by determination of the lysine residue number, positive charge and molecular length of obtained fragments by the method of incomplete succinylation. It has been shown, that Anodonta histone H1, like the avian histone H5, contains 3 tyrosine residues in the central hydrophobic domain of the molecule. Histone Hp contains 5 tyrosine residues, 3 of which are localized in the hydrophobic domain, while the rest two--in the COOH-terminal part of the molecule, characterized by a strong positive charge. Such unusual disposition of tyrosine residues in the lysine-rich histone has been found for the first time. All the regions of histone Hp molecule contain a great number of arginine residues. The only phenylalanine residue is localised approximately in the middle of the polypeptide chain for both H1 and Hp molecules. On the basis of structure homology between histones H1 and Hp the origin of Hp from H1 in the course of evolution is proposed.


Assuntos
Histonas/análise , Lisina/análise , Moluscos/metabolismo , Espermatozoides/análise , Sequência de Aminoácidos , Animais , Eletroforese em Gel de Poliacrilamida , Histonas/isolamento & purificação , Hidrólise , Masculino , Peptídeos/análise
12.
Biokhimiia ; 47(8): 1378-85, 1982 Aug.
Artigo em Russo | MEDLINE | ID: mdl-6812653

RESUMO

A simple method for determination of lysine residue number and positive charge of histones H1 and H5 in the acetic acid -- urea system has been developed. The method is based on incomplete succinylation of lysine residues and allows an accurate determination of protein molecular length. The accuracy of the method has been demonstrated by determination of goose and chicken histones H5 and their fragments. The calibrating curve for determination of molecular lengths of histones H1 and H5 has been plotted. Using the incomplete succinylation method, a detailed analysis of Lymantria dispar histone H1 structure has been carried out. The method under discussion can be used for determining lysine residue number, positive charge and molecular length of practically any protein.


Assuntos
Histonas , Lisina/análise , Acilação , Animais , Bromosuccinimida , Fenômenos Químicos , Química , Galinhas , Gansos , Indicadores e Reagentes , Peso Molecular , Mariposas
13.
Mol Gen Genet ; 254(5): 592-8, 1997 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-9197420

RESUMO

Two Fix- mutants of pea (Pisum sativum L.) which are unable to fix molecular nitrogen, E135f (sym-13) and Sprint-2Fix- (sym-31), were crossed to create the doubly homozygous recessive line, named RBT (sym-13, sym-31). The ultrastructural organization of nodules of the RBT line was compared with that of each of the two parental mutant lines and with the original wild-type genotypes of the cultivars Sparkle and Sprint-2. It was shown that the RBT line is similar to the mutant line Sprint-2Fix- in having abnormal symbiosome composition and bacteroids with relatively undifferentiated morphology. Because the phenotypic manifestation of the sym-31 mutant allele suppresses the phenotypic manifestation of the sym-13 mutant allele, it is concluded that the function of the gene Sym-31 (which is mutated in the Sprint-2Fix- line) is necessary at an earlier stage of symbiosome development than the gene Sym-13 (which is mutant in the E135f line).


Assuntos
Genes de Plantas/genética , Pisum sativum/microbiologia , Raízes de Plantas/microbiologia , Rhizobium/fisiologia , Simbiose/genética , Mutação , Pisum sativum/genética , Raízes de Plantas/ultraestrutura , Rhizobium/ultraestrutura
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